The present invention relates to a shock absorbing structure for protecting a driver and passengers from secondary collisions when a vehicle collides with something. More particularly, the present invention pertains to a shock absorbing structure that includes a shock absorber between an outer panel and a garnish panel of a vehicle.
When a vehicle collides with something, two measures, or primary and secondary measures, are taken to protect passengers. The primary measure refers to a structure for permitting the vehicle body to directly absorb shock. The secondary measure refers to a structure for preventing a driver and passengers from being injured when they hit something in the passenger compartment due to the collision.
A shock absorbing structure of the second measure preferably absorbs a great shock with a small deformation while suppressing the load applied to the driver or the passengers lower than a predetermined level. Japanese Unexamined Patent Publication No. 2000-85503 discloses a shock absorbing structure. The structure of the publication includes a hollow shock absorber that has a predetermined cross section. The shock absorber is located in a shock absorbing space, which is defined between an inner panel that forms an pillar and a garnish that covers the pillar.
The shock absorbing structure of the publication effectively absorbs a shock applied along a predetermined single direction. Specifically, if a driver on the driver""s seat the pillar at the driver""s seat, the shock is effectively absorbed. However, if a passenger on the other front seat hits the pillar at the driver""s seat, the shock may not be effectively absorbed because the direction of the load is different from the predetermine direction. Also, if the driver hits the pillar at the other front seat, the shock is not effectively absorbed.
FIG. 4 is a graph showing the relationships between load and deformation of shock absorbing structures. The relationships of the graph were obtained through simulations. Double-dashed line represents a case of a prior art structure where a passenger on the front passenger seat hits the pillar at the driver""s seat of a vehicle. In this case, shock is not effectively absorbed.
Accordingly, it Is an objective of the present invention to provide a shock absorbing structure that effectively absorbs shocks along two directions to prevent a driver and passengers from being injured.
To achieve the foregoing and other objectives and in accordance with the purpose of the present invention, a shock absorbing structure having a shock absorber that is accommodated in a space defined between an inner panel and a garnish panel of a vehicle to absorb shock due to a secondary collision between the vehicle and a passenger is provided. The shock absorber includes a hollow main body, a plurality of walls that form the main body and a projection that protrudes outward or inward. When receiving shock along a first direction, the shock absorber is deformed to fold the projection. When receiving shock along a second direction, the shock absorber is deformed to unfold the projection.
Other aspects and advantages of the invention will become apparent from the following description, taken in conjunction with the accompanying drawings, illustrating by way of example the principles of the invention.